The reason why the color of the product is not normal after heat treatment in vacuum furnace

Vacuum furnace is the mainstream equipment in the heat treatment industry at present, the products processed by it are not only reliable in quality, but also environmentally friendly and pollution-free, and do not need to carry out three wastes treatment, and the energy consumption is significantly lower than that of traditional heat treatment equipment such as salt bath furnace. Therefore, it is widely used in aerospace, weapons, electronics, automobiles, machinery industry and other fields. However, it is often seen that vacuum furnace users post on the Internet to ask about the wrong color of the product out of the vacuum furnace heat treatment. This problem is a common problem in the heat treatment production. Today, vacuum Equipment Co., Ltd. briefly analyzes the causes and solutions for the wrong color of the product treated by the vacuum furnace.

First of all, we can detect whether the vacuum furnace equipment itself has gas leakage, which can be determined by the pressure rise rate index of the vacuum furnace; It is necessary to remind everyone that when testing the pressure rise rate, it must be tested after the oven is cooled to room temperature, and it cannot be vacuumed after opening the furnace door for testing.

Sometimes we test the pressure rise rate of the vacuum furnace is normal, but there is leakage in the intake pipe or valve of the vacuum furnace, and the pressure in the intake pipe is gradient, the closer to the end of the furnace body is the more negative pressure, which is also one of the reasons for the wrong color of the product processed by the vacuum furnace.

The reason and solution of the color of the product produced by the heat treatment of vacuum furnace are wrong

Third, we can detect the purity of the inert gas into the vacuum furnace equipment is not high, when the purity of the inert gas is not enough, the oxygen mixed in it will lead to the oxidation of the product, decarbonization and other behaviors, resulting in product discoloration. The purity of the detected gas can be directly detected or compared by other equipment to draw conclusions.

Finally, the moisture in the vacuum furnace equipment is attached to the inner wall of the vacuum furnace or the heat exchanger above, this moisture is difficult to discharge through the oven method, when the vacuum furnace equipment does not have the above three problems, the color of the product is not correct, most of the reason is caused by this; At this time, we can raise the vacuum furnace equipment to a high temperature, stop heating, and then pass high-purity inert gas into the furnace, and then start the fan circulation system, and use the high temperature and hot air in the vacuum furnace to bake out the moisture attached to the inner wall of the vacuum furnace and the heat exchanger, so as to solve the problem.